An analog-to-digital converter (ADC) is a device that converts an analog input signal to a digital output signal comprising a sequence of bits that represent an amplitude of the analog input signal. An ADC typically has an analog reference voltage or current against which the analog input signal is compared. The digital output signal indicates what fraction of the reference voltage is the amplitude of the analog input signal. Analog-to-digital converters (ADCs) are widely used by modern day digital electronic systems to convert analog signals to digital signals that can be used by the digital electronic systems.